This invention relates to the automatic threading of tape into a tape transport system of the type described, for example, in U.S. Pat. No. 3,370,803. In such systems two tape packs are wound on and unwound from hubs on shafts which are rotatably mounted on carriages. The carriages are slideable toward and away from the capstan as the diameter of the supply tape pack decreases and that of the take-up pack increases, these two carriages being urged toward and the tape packs being driven by the capstan. The supply reel must be equipped with a self threading leader of the type described, for example, in U.S. Pat. No. 3,773,276. The leader includes a series of pre-formed fingerlike gripping tabs which engage either the side edges of convolutions of a reel of tape to keep it wrapped, or alternatively, the outer periphery of a take-up hub to start the leader winding around said hub.
The procedure for threading the tape with such a leader into the tape transport unit requires several steps, including (1) assuring that the leader is properly seated on the supply reel, (2) peeling the leader off the supply reel, (3) feeding the leader through the tape guides past the recording head, (4) starting to wind the leader around the take-up hub, and (5) removing the slack from the system. In terms of convenience it is desirable to have as many of these operations performed automatically as possible. The present invention performs all of the above threading operations not only automatically in the sequence indicated but also quickly and reliably.